If I were you I'd take the new job which is just down the road (once I'd confirmed that it was a firm offer, in writing, and was definitely a done-deal).
If asked (in future) why you were only in your current job for sixth months, you can just say part of what you'd said above. It was a long commute and was work that you didn't particularly enjoy or feel comfortable doing. You realised this quite early on, but felt that the right thing to do was to stick with it to see if the situation improved. It didn't, so after six months you decided that it was to move on.